Process of purifying water.



- called allophanoids.

UNITED STATES PATENT OFFICE.

VALERIUS KOBELT, OF BERLIN GEBMANY.

PROCESS OF PUBIFYING WATER.

Specification of'Letters Patent.

Patented Aug. 6, 1918.

No Drawing. Original application filed February 26, 1912, Serial No. 680,132. Dividedand this application filed August 14, 1912. Serial No. 715,072.

To all whom z't may concern:

Be it known that I, VALERIUs KoBELT, a

subject of the King of Prussia, and resident.

In the purification of water various crystalline substances bothnatural and artificial have been heretofore used such as for example, the natural and artificial zeolites, mica, etc. According to the novel process of the present invention waterispurified by the use, instead of such crystalline-bodies as those indicated, of amorphous substances obtained from natural rock and particularly from porous volcanic roclr, namely the so These in their purifying action considerably surpass the crystalline zeolites and other agents heretofore used.

The allophanoids are non-crystalline minerals, sometimes called amorphous glass'and their main constituents are alumina, silicic acid and water.

' According to the present invention these allophanoids which are in their nature amorphous and colloidal are used for the purification of water, highly advantageous results being thu's obtained.

Such amorphous bodies, the useof which forms the subject of the present invention and which for the purpose of this invention are hereinafter referred to as the purifying medium, are not crystalline minerals, but are the non-crystalline or amorphous constituents found in nature in certain volcanic rocks and in Germany are generally termed gesteinsglaser. Whereas the zeolites as well as the crystalline products hitherto proposed for the purification of Water representchemical compounds, the gesteinsgliisei are mixtures of extremely varying composition which during their formation never reach the stage of solid chemical compounds and which in the art or science were consequently-termed as solid solution. The main constituents of the purifying medium, used according to this invention are aluminium, silicic acid, Water and metals (preferably alkalis and earth alkalis) the quantitative relation of these constituents varying within wide limits.

From the artificial or also-from the nat-- ural zeolites these substances differ distinctly by their behavior with regard to acids.

Whereas all zeolites artificial or natural show'the feature characteristic for all zeolites viz: of being decomposed by hydrochloric acid forming a silicious jelly, this purifying medium is practically indifferent to diluted hydrochloric acid which shows that this medium is not a zeolite and that itdoes not contain any zeolites, although it 1s affected by concentrated acid when heated, in which case the bases (alkalis, earth alkalis) are gradually dissolved out but ,can be re-introduced .bysubsequent treatment with alkali solutions.

The alloplianoids used according to the process of the present invention can be obtained from porous volcanic rock by grinding this rock to a line condition and separating the allophanoids from the finely ground material by elutri-ation. The finely ground material may in'the same way be mixed with Water and agitated or made up into a paste and diluted with water and the finer and lighter constituents removed by decanting from the heavier material which separates and settles 'to the bottom. The separation 'can advantageously be carried out in a series of steps by agitating the material in water which flows continuously from one receptacle to another carrying with it the lighter constituents from which the heavier impurities settle gradually. In this way the lighter material containingthe allophanoids becomes purer and purer and a substance is obtained which consists essentially of the active material with only a very small amount of the inactive material or none at all.

The allophanoids thus obtained can be used for freeing water quantitatively from lime salts and magnesia salts by simply filtering the water through it.

Again the allophanoids can be mixed with the Water and allowed to settle. Other impurities can also be removed such as for eX- purification plant o of the filter body can be correspondingly decreased. 'A iurther a dvantage of the process of the present invention. is that undesirable purifying tendon: cies are counteracted.

This application is a division of my application Ser. No. 680,132, filed February 26, 1912.

I claiin:

l. The process of purifying water, which:

comprises subjectingthe water to the action of natural non-crystalline colloidal allophanoid (gestemsgliiser) freed from granular material and nnpurities.

3. The process of purifying water, which comprises subjecting the water to the action of natural non-crystalline, colloidal allophanoid- (gesteinsglaserf washed free from granular material and impurities, said allophanoid being insoluble in dilute hydro-' chloric acid. f I

l. The process of purifying water which comprises subjecting the water to the active constituents only. of natural non-crystalline colloidal allophanoids and freed from gran-, ular and inactive materials, sald active constituents being insoluble in dilute hydrochloric acid and non-freezing.

' In testimony whereof I aflix my signature in presence'of two witnesses.

VALERIUS KOBELT.

Witnesses HENRY HAsPER, ARTHUR SCHROEDER. 

